Numerous applications, such as detector and display arrays, require imaging an object onto a flat surface with spot-size (i.e., point spread function or “PSF”) that is about less than or equal to the wavelength of the incident electromagnetic wave, and with large field of view. Customarily, traditional optics comprising the capability to image in such applications are bulky, heavy, generally include several complex lenses and refractive and/or reflective elements, are expensive to manufacture, and troublesome to operate.
An apparatus that produces spot-size that is about less than or equal to the wavelength of the incident electromagnetic wave is the photonic jet. A prior art photonic jet is depicted in FIG. 1. A photonic jet is a dielectric sphere having proper optical refractive index to focus an incident plane electromagnetic wave into a rod of light (i.e., the Fourier transform of the incident plane electromagnetic wave), the beam having a length about as great as the diameter of the Fourier transformed incident plane electromagnetic wave.
The use of the photonic jet to image onto a flat surface is not without limitation. Referring to FIG. 1, the photonic jet focuses light into a spherical surface. As illustrated in FIG. 1, the exit point of the Fourier transformation of an incident plane electromagnetic wave (i.e., the rod of light) is dependent upon the angle of incidence of the plane electromagnetic wave with respect to the projection plane. Thus the Fourier transformation of an incident plane electromagnetic wave produced by a photonic jet does not necessarily have a wide field of view. This lack of wide field of view represents a major limitation in many applications, such as when imaging conventional detector and display arrays, since conventional detector and display arrays are built on flat surfaces.